PlaceholderSigns/src/main/java/net/knarcraft/placeholdersigns/PlaceholderSigns.java

package net.knarcraft.placeholdersigns;

import me.clip.placeholderapi.PlaceholderAPI;
import net.knarcraft.placeholdersigns.command.EditSignCommand;
import net.knarcraft.placeholdersigns.container.LineChangeRequest;
import net.knarcraft.placeholdersigns.container.PlaceholderSign;
import net.knarcraft.placeholdersigns.handler.PlaceholderSignHandler;
import net.knarcraft.placeholdersigns.listener.SignBreakListener;
import net.knarcraft.placeholdersigns.listener.SignClickListener;
import net.knarcraft.placeholdersigns.listener.SignTextListener;
import net.md_5.bungee.api.ChatColor;
import org.bukkit.Bukkit;
import org.bukkit.Location;
import org.bukkit.block.Sign;
import org.bukkit.command.PluginCommand;
import org.bukkit.configuration.serialization.ConfigurationSerialization;
import org.bukkit.entity.Player;
import org.bukkit.plugin.java.JavaPlugin;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

import java.util.HashMap;
import java.util.Map;
import java.util.logging.Level;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * This plugin's main class
 */
public final class PlaceholderSigns extends JavaPlugin {

    private static PlaceholderSigns instance;
    private PlaceholderSignHandler signHandler;
    private Map<Player, LineChangeRequest> changeRequests;

    /**
     * Gets an instance of this plugin
     *
     * @return <p>A plugin instance</p>
     */
    public static @NotNull PlaceholderSigns getInstance() {
        return instance;
    }

    /**
     * Gets this instance's placeholder sign handler
     *
     * @return <p>The sign handler</p>
     */
    public @NotNull PlaceholderSignHandler getSignHandler() {
        return this.signHandler;
    }

    /**
     * Registers a sign change request
     *
     * <p>A sign change request is basically the result of running the editSign command, which must be stored until the
     * player clicks a sign.</p>
     *
     * @param request <p>The sign change request to register</p>
     */
    public void addChangeRequest(@NotNull LineChangeRequest request) {
        changeRequests.put(request.player(), request);
    }

    /**
     * Gets a sign change request
     *
     * @param player <p>The player to get the request for</p>
     * @return <p>The sign change request, or null if not found</p>
     */
    public @Nullable LineChangeRequest getChangeRequest(@NotNull Player player) {
        return changeRequests.remove(player);
    }

    @Override
    public void onLoad() {
        super.onLoad();
        // Register serialization classes
        ConfigurationSerialization.registerClass(PlaceholderSign.class);
        ConfigurationSerialization.registerClass(PlaceholderSignHandler.class);
    }

    @Override
    public void onEnable() {
        instance = this;
        signHandler = new PlaceholderSignHandler();
        changeRequests = new HashMap<>();
        signHandler.load();

        if (Bukkit.getPluginManager().getPlugin("PlaceholderAPI") == null) {
            getLogger().log(Level.WARNING, "Could not find PlaceholderAPI! This plugin is required.");
            Bukkit.getPluginManager().disablePlugin(this);
            return;
        }

        // Update signs' placeholders every second
        Bukkit.getScheduler().runTaskTimer(this, this::updateSigns, 20 * 10, 20 * 5);

        Bukkit.getPluginManager().registerEvents(new SignBreakListener(), this);
        Bukkit.getPluginManager().registerEvents(new SignTextListener(), this);
        Bukkit.getPluginManager().registerEvents(new SignClickListener(), this);

        PluginCommand editCommand = Bukkit.getPluginCommand("editSign");
        if (editCommand != null) {
            editCommand.setExecutor(new EditSignCommand());
        }
    }

    @Override
    public void onDisable() {
        // Plugin shutdown logic
    }

    /**
     * Updates all loaded and registered placeholder signs
     */
    private void updateSigns() {
        for (PlaceholderSign placeholderSign : signHandler.getSigns()) {
            // Ignore signs away from players
            Location location = placeholderSign.location();
            if (!location.getChunk().isLoaded()) {
                continue;
            }

            // If no longer a sign, remove
            if (!(location.getBlock().getState() instanceof Sign sign)) {
                signHandler.unregisterSign(placeholderSign);
                continue;
            }

            // Update placeholders
            Map<Integer, String> placeholders = placeholderSign.placeholders();
            String[] lines = sign.getLines();
            boolean updateRequired = false;
            for (int i = 0; i < lines.length; i++) {
                String oldText = sign.getLine(i);

                // The new text of the sign is either the same, or the original placeholder
                String newText;
                if (!placeholders.containsKey(i) || placeholders.get(i) == null) {
                    newText = oldText;
                } else {
                    newText = PlaceholderAPI.setPlaceholders(null, placeholders.get(i));
                }

                // Convert color codes
                newText = translateAllColorCodes(newText);

                // Only change the line if the text has changed
                if (!newText.equals(oldText)) {
                    sign.setLine(i, newText);
                    updateRequired = true;
                }
            }

            // Only update the sign if the text has changed
            if (updateRequired) {
                sign.update();
            }
        }
    }

    /**
     * Translates all found color codes to formatting in a string
     *
     * @param message <p>The string to search for color codes</p>
     * @return <p>The message with color codes translated</p>
     */
    private static String translateAllColorCodes(String message) {
        message = ChatColor.translateAlternateColorCodes('&', message);
        Pattern pattern = Pattern.compile("&?(#[a-fA-F0-9]{6})");
        Matcher matcher = pattern.matcher(message);
        while (matcher.find()) {
            message = message.replace(matcher.group(), "" + ChatColor.of(matcher.group(1)));
        }
        return message;
    }

}